1. Field of the Invention
The present invention relates generally to the glass cutting art and more specifically to a press roll for breaking out a prescored glass pattern from a larger sheet or bracket of glass.
2. Description of the Prior Art
In manufacturing automotive vehicle windows which involve a variety of shapes, it is desirable to make a clean break of a prescored glass pattern so that the periphery of the cut-out or broken-out pattern has smooth perpendicular edges free of chips or nicks. One way of doing this is to rollably move a pressing roll over a prescored glass bracket supported on a rigid breakout template as disclosed in U.S. Pat. No. 3,770,173, issued on Nov. 6, 1973.
The pressing roll described in the aforementioned patent is a weighted pliable elongated roller having a relatively thin fluid-type resilient housing of rubbery material filled with a fluid. The resiliency of the housing and the fluid filling provides a sausage-like roller structure tending to sag at its central portion which passes over the central portion of the glass bracket. However, the sausage-like roller has not proved to be entirely satisfactory for its purpose in that it causes the prescored glass bracket to be loaded by statically unpredictable forces making it difficult, if not impossible, to regulate the forces acting on the glass bracket to cleanly break out the prescored pattern. Furthermore, the resilient housing of the pressing roll is subject to punctures by the broken jagged selvage edges of the glass bracket which, of course, results in loss of the fluid filling which necessitates replacement of the roll and, thus, loss of production time.